German Published Patent Application No. 199 51 362 discusses a method for regulating the cooling water temperature, a temperature sensor detecting the cooling water temperature and a control unit for the cooling water temperature actuating at least one valve and/or one fan in order to obtain a predetermined temperature setpoint value of the cooling water, a further sensor and/or an engine or vehicle control unit being provided whose signals are fed to the first control unit, the first control unit determining a temperature setpoint value therefrom. The determination of the setpoint value may be predetermined as a function of the driver type, a driver who drives sportily or economically, for example.
In this manner, the exhaust gas value and the fuel consumption may be optimized and/or minimized.
Furthermore, German Published Patent Application No. 41 09 498 discusses regulating the temperature of an internal combustion engine so that different temperature setpoint value ranges are used for the temperature regulation on the basis of different operating conditions. In particular, operating parameters of the internal combustion engine, among other things switching on of auxiliary systems and malfunctions of the internal combustion engine, may be cited as operating conditions. The setpoint value of the cooling water temperature may be set depending on which priority the different operating conditions have.